[openmpi] find_package(MPI) doesn't work correctly for debug configuration

[dg0yt]

Describe the bug

When trying to enable netcdf-c utilities with parallel hdf5 (work in progress), the following warning is issued to stderr:

CMake Warning at /home/dg0yt/Projekte/vcpkg/vcpkg/scripts/buildsystems/vcpkg.cmake:664 (_add_executable):
  Cannot generate a safe runtime search path for target ncgen because there
  is a cycle in the constraint graph:

    dir 0 is [/home/dg0yt/Projekte/vcpkg/vcpkg/installed/x64-linux/debug/lib]
      dir 1 must precede it due to runtime library [libmpi.so.40]
    dir 1 is [/home/dg0yt/Projekte/vcpkg/vcpkg/installed/x64-linux/lib]
      dir 0 must precede it due to runtime library [libmpi.so.40]

  Some of these libraries may not be found correctly.
Call Stack (most recent call first):
  ncgen/CMakeLists.txt:23 (ADD_EXECUTABLE)

I assume this is caused by the way how MPI is used with CMake. CMake's FindMPI.cmake relies on finding an MPIEXEC_EXECUTABLE via find_program. But even for debug builds, CMAKE_PROGRAM_PATH doesn't guide cmake to look for the tool in tools/openmpi/debug. So the release tools are found and used, leading to the mix release and debug configuration.

Environment

• OS: Linux

To Reproduce

$ ./vcpkg install hdf5[parallel]
$ cat buildtrees/hdf5/*-dbg/CMakeCache.txt  | grep MPIEXEC_EXECUTABLE:
MPIEXEC_EXECUTABLE:FILEPATH=/home/dg0yt/Projekte/vcpkg/vcpkg/installed/x64-linux/tools/openmpi/bin/mpiexec

Expected behavior

$ ./vcpkg install hdf5[parallel]
$ cat buildtrees/hdf5/*-dbg/CMakeCache.txt  | grep MPIEXEC_EXECUTABLE:
MPIEXEC_EXECUTABLE:FILEPATH=/home/dg0yt/Projekte/vcpkg/vcpkg/installed/x64-linux/tools/openmpi/debug/bin/mpiexec

Additional context

Package installation layout for tools #17607

[JackBoosY]

For tools, I don’t think we need to use the debug version, because its performance is much lower, and it can’t help us to debug.

BTW, I can confirm this issue.

[dg0yt]

For tools, I don’t think we need to use the debug version, because its performance is much lower, and it can’t help us to debug.

I can agree for gettext tools, moc and similar. But there are tools which carry lib path and linkage information:

• curl-config
• geos-config
• qmake

and probably this is true also for some or all MPI tools? FindMPI.cmake is non-trivial IIRC.

[Osyotr]

Hit me today with:

1> [CMake] CMake Warning at /home/me/development/vcpkg/scripts/buildsystems/vcpkg.cmake:596 (_add_library):
1> [CMake]   Cannot generate a safe runtime search path for target my_target because there
1> [CMake]   is a cycle in the constraint graph:
1> [CMake] 
1> [CMake]     dir 0 is [/mnt/d/my_project/out/build/WSL-GCC-Debug/vcpkg_installed/x64-linux/debug/lib]
1> [CMake]       dir 1 must precede it due to runtime library [lib7zip.so]
1> [CMake]     dir 1 is [/mnt/d/my_project/out/build/WSL-GCC-Debug/vcpkg_installed/x64-linux/lib]
1> [CMake]       dir 0 must precede it due to runtime library [libQt5Core.so.5]
1> [CMake] 
1> [CMake]   Some of these libraries may not be found correctly.
1> [CMake] Call Stack (most recent call first):
1> [CMake]   CMakeLists.txt:15 (add_library)